Multicontact switch



Sept. 15, 1964 J. P. wATsoN MuLTIcoNTAcT SWITCH Original Filed April 2,1956 FIGS . //M/,../////////7//// l/A` INVENTOR Sept. l5, 1964 v J. P.wATsoN 3,149,209

MULTICONTACT SWITCH Original Filed April 2, 1956 5 Sheets-Sheet 2 FIGy 5sept. 1s, 1964 J. P. WATSON 3,149,209

MULTICONTACT SWITCH Original Filed April 2. 1956 5 Sheets-Sheet 5 FI yROTATIONAL MOVEMENT INVENT OR United States Patent 3,149,209MULTICONTACT SWITCH .lames P. Watson, Whittier, Caiif.

(59 Waterway Road, Waterway Village, `Inpiter, Fia.) Originalapplication Apr. 2, 1956, Ser. No. 575,467, new

Patent No. 2,964,602, dated Dec. 13, 1960. Divided and this applicationApr. 1, 1960, Ser. No. 24,192

2 Claims. (Cl. 200 6) This invention relates primarily to snap actingmechanisms, and more particularly to a snap acting leaf-springtypeelectric switch.

It is an object of this invention to provide a snap acting mechanismhaving a very long operating life.

This application is -a division of application Serial No. 575,467 whichhas now issued as Patent 2,964,602.

It is .another object of this invention to provide such a mechanism ofsimple structure having a minimum number of separate parts.

It is another object of this invention to provide a snap actingmechanism, `and particularly a snap yacting switch having compact sizeand low weight compared to its current-breaking capacity.

It is another object of this invention to provide a snap actingmechanism which may be effectively operated by shaft rotation with aminimum complexity between the rotating shaft and the snapping action ofthe switch.

In modern engineering the importance of small or miniature switch isgrowing rapidly. Such switches, although themselves small, yaregenerally complicated by the fact that the operating means or mechanismfor the switch is so cumbersome as to vitiate largely theminiaturization of the switch itself.

It is an object of this invention to provide `an integrated switch landoperating mechanism which together will be small -in weight and bulk andsimple in operation.

It is another object to provide a switch and operating mechanism asabove which is uniquely adapted for the oper-ation of the switch byrotary motion, yas through a shaft.

It is another object of this invention to provide a switch and operating.assembly as above wherein a number of such assemblies may be gangedtogether for operation from a single shaft.

It is another object of this invention to provide a cam mechanismincluding a shaft which may be moved either rotationally or axially tocause a cam to operate upon a cam follower.

It is another object of this invention to provide `a mechanism as abovewherein the cams on the shaft m-ay be readily interchanged to introducea diiferent cam follower action pattern. A..

It is a further object of this invention to` provide an yassembly ofsnap acting switches of compact bulk and weight which may be operatedfrom a single shaft.

In `accordance with these and other objects which will become apparenthereinafter, preferred forms of the present invention will now bedescribed in connection with the accompanying drawings wherein:

FIG. 1 is la perspective view illustrating a multi-switch form of thepresent invention;

FIG. 2 is a fragmentary cross-section of the switch shown in FIG. 1;

FIG. 3 is a sectional View taken on line 3 3 in FIG. 2;

FIG. 4 is a cross section of a modified form of cam actuating mechanismfor the switch shown basically in FIG. l;

FIG. 5 is a cross section taken on line 5 5 in FIG. 4;

FIG. 6 is a cross section taken on line 6 6 in FIG. 5;

FIG. 7 is a cross section taken on line 7 7 in FIG. 5;

FIG. 8 is a fragmentary section taken generally in the same plane asFIG. 5, showing the manner in which two switches of the kind shown inFIG. 5 may be ganged together to be operated by a single shaft means;

FIG. 9 is an enlarged View of that portion shown at 9 in FIG. 8; and

FIG. 10 is Xa cross section taken on line 10 10 in FIG. 9.

In FiGS. l-3, the switch of the present invention has been shown adaptedinto a multi-contact switch consisting of a plurali-ty of members 4allactuated from a single rotating shaft. As shown in FIG. 2, the severalleaf members 36j are disposed radially, i.e., in spoke fashion, about acenter opening 148 through which the operating shaft extends. Each ofthe leaf members 36f has associated therewith four terminals 98]c whichproject radially out of the circular housing 62j.

Each pivot shaft 39]c is provided with a curved camfollower arm 6'7fterminating in a ball 681 which rides against a preselected cam 69f. Aplurality of cams 69j are provided disposed axially upon the sleeve73]", each cam 69f serving to actuate one of the arms 67f. Each cam 69jis splined to the sleeve 73j as shown at 149 so that it may be removedfrom the sleeve 73] and readjusted thereon in any angular positiondesired.

The ball heads 68f are all biased radially inward by means of `torsionsprings 151 encircling the respective pivot shafts 391 and having theirends embedded in the respective frame arms 43j with the intermediateportions of the springs 151 ybearing resiliently against the respectivearms 67]c to bias the ball heads 68j inwardly.

Each of the cams 69f is cut in any desired fashion, so that at anydesired predetermined angular position, the corresponding arm 67 f isforced outward with consequent snapping of the associated leaf 361i, andallowed to drop back under urging of the spring 151 wherever Ithe cam69j is relieved inward. Each cam 691c thus has -a surface 152 ofrelatively small radius and a surface 153 of relatively large radius.

To isolate each leaf 36)c electrically, each pivot shaft 39j isjournaled in a pair of insulating grommets 154 in which is likewisesecured the projecting ends of each spring 151. The upper end of theleaf is also insulated by a suitable insulating grommet 156. If desired,these insulating points may be deliberately by-passed by respectiveiiexible pigtail members 157 connected between each leaf 36)c and itscorresponding frame 421.

To adapt the switch selectively for a wide variety of applications, thelower end of each of the frame arms 43] may be connected to or madeintegral with a common ring 158 from which extends radially a commonterminal 159.

In this way, if desired, current may be selectively fed from a singleinput terminal 159 to any pair of associated terminals 981 in anydesired pattern of operation, depending upon the shape and placement ofthe cams 69j.

This use of the switch employs the several radial leaf spring members36j as distributing arms.

Whenever it is desired that the switch leaves 36)c be electricallyisolated, it is only necessary to remove the pigtails 157, thusisolating the terminal 159 and allowing each of the switches to operateelectrically independently.

It will be clear that where the common terminal 159 is employed, andconnected to each of the leaves 36), the insulating grommets 154 and 156may, if desired, be omitted.

The switch shown in FIGS. l-3 also illustrates a manner of pivotallymounting the upper or outer end of the leaf members 36j.

In the switch shown in FIGS. 1 3, the pivot pin 51f is formed integralwith the upper shaft 47]c and is journaled in the cross piece 44fthrough the intermediacy of the insulating sleeve or grommet 156 alludedto hereinbefore. To permit the necessary slight pivoting of the :igshaft 47j the cross piece idf is then journaled at each end 164iV in theupper ends of the respective arms 431,

The shaft 471 projects into the windows or opening 93] formed in thearms 4131 to prevent excessive twisting of the upper end of the leaf 36jwhich might cause diagonal bridging of the stationary contacts 97j.Forthose uses of this switch where the leaf Snf must be'electricallyisolated, it is thus necessary to provide insulating bushings 165 ateach side of the windows 93j to prevent electrical contact between theshaft 471 and the frame arms 431i.

InFIGS. 4-7, there is illustrated a modification of the pancake orradial type switch illustrated in FIG. l. In

this form, the cam action is effected by a plurality of individual cammembers 69g. Each cam is provided with a T-section base 166 adapted toslide into an undercutV groove 167 of similar shape formed axially inthe surface of a cylinder 163 forming the shaft means carrying the cams69g. A plurality of such axial grooves 167 are formed in the cylinder168, completely therearound, so that if and when each groove 167 iscompletely occupied with cams 69g, the entire surfacel of the cylinder16@ is overlaid with cams. In order to achieve the necessary back andforth movement of the cam follower arms 67g, spacers 169 are provided asalternates to the cams 69g. The spacers 169 are identical with the baseportions 166 of the cams 69g. Thus wherever a spacer 169 is used theball 68g of the cam follower drops down on the spacer 169, even with thesurface of the cylinder 168. In this manner, any desired cam pattern maybe placed on the surface of the cylinder 163 varying bothcircumferentially and axially.

means carrying the cams 69g i.e. the cylinder' 1%, as well as to permitmovement of the shaft means to a given axial and rotative setting,without running through all of the intervening switch sequences. This isa means for lifting and holding all of the switch arms 67g away from thecams 69g, and Vconsists of a ring 184- mounted circumjacent the severalauxiliary or operating shafts 39g carrying the respective follower arms67g. Each shaft 39g has a short arm 1&6 projecting radially therefrom. Apivot pin 137 links the outer end of each arm 186 through a slot 18S tothe ring 1h11. As shown in FIG. 7, when the ring 184 is rotatedclockwise each of the arms .1S- is likewise pivoted slightly clockwisecausing The cylinder 168 has an axial bore 171 which lits slid-V v ablyover an axial stud 172 projecting into the housing of the switch fromthe external wall 17 3. The cylinder 16S is thus mounted over the stud172 for both axial and rotative movement.

Three circumferential rows of detents 174 are provided at the forwardend of the cylinder 168 in which seats a spring pressed ball 176 mountedin the housing wall 177. By means of an external knob 178 the cylinder16% may thus be rotated to bring the cams 69g rotatively into engagementwith the various earn followers 68g. In the embodiment shown thecylinder 16% may also be pulled out in two steps, thereby bringing thecams 69g axially into engagement with the cam followers 68g. The switchis thus readily adapted for operation either by rotation or axialreciprocation of the cylinder 168. If desired, both methods of operationmay be successively employed. Thus rotation of the knob 178 produces agiven switching pattern depending on the placement of cams 69g andspacers 169. By pulling the knob 17S out one notch, a second pattern iseffected. In similar fashion pulling the knob 173 out another notcheffects a third rotary switch pattern.

When the knob 17 8 is pulled out one notch, the numeral Z is visible onthe cylinder 16d to show the operator that the knob is in the number 2axial position; similarly further pulling out of the knob 173 revealsthe numeral 3 to indicate that the switch is in the third axialposition.

VAn indexing arrow 179 on the circumferential surface of the knob 175Bcooperates with a plurality of numbered radial lines 181 imprinted onthe wall 177 to indicate the rotational position of the switch.

The cams 69g and spacers 169 are held in place against radial andtangential movement by the natural mating configuration of the undercutslot and corresponding shape of the base or spacermember. They are heldagainst axial movement by being stacked against each other, the entirestack being held in place by a recessed cap 182 held in place by threecounter sunk flathead bolts 183 threaded into the end of the cylinder16S.

As in the switch shown in FIG. l et seq., the follower arms 'grarebiased inwardly toward the cylinder 168 by individual torsion springs151g. Means are provided for simplifying removal and replacement of theshaft a corresponding pivoting of each shaft 39g with consequentpivoting of each arm 67g away from the cams 69g. The slots 133 permiteach shaft 39g, in normal opration, to pivot individually withoutaffecting the ot ers.

Rotation of the ring 184 is effected through a finger 189 threaded intothe ring 1&2- and projecting through a radial slot 191 in the wall 177.

The switch of FIG.V 5 is so constructed' and designed that a number ofsuoli switches may be ganged together in alignment to be operated by asingle operating knob 17S. The manner in which this is accomplishedwillbe explained by assuming that the switch shown in FIG. 5 is to havesecured tothe end thereof an identical switch whose parts or elementswill be referred to by the samel numerals as are contained in FlG. 5 butcarrying a prime.

To adapt the switch of FIG. 5 for the ganging arrangement mentionedabove, the forward end of the cylinder 168 isrmade of a separate part193, to which the knob 17t3'is secured or made a part of. The partingline between the cylinder 168 proper and its front end 195 is shown at19d. The bores for the bolts 133 are-made smooth in the lcylinder 163proper and are tapped only in the forward section 193. In this manner,bolts 133 serve the double function of holding the retaining cap 1152 inplace and also of securing the front end of the cylinder 193 to thecylinder proper 16%.

The iirst step in ganging two switches together is to remove the rearwall 173 which forms the outer case for the switch. This operation ofcourse also removes the stud 172. As explained hereinbefore, the bolts183 are spaced around the cylinder 16S, but as shown in FIG. 4, thisspacing is not symmetrical, thereby providing a unique keyingrelationbetween the cylinder 168 and the knob 17? carrying the index 179.Removal of the rear wall 173 exposes three additional bores 1% (FIG. 4)in the rear end of the cylinder 16S, these bores being tapped in thesame manner as the front cylinder portion 193. The flat heads of thebolts 133 are recessed in the cap 182, as shown in FlG. 5, and the rearface of the cylinder 16S is thus ready to receive riush thereagainst thefront face of its homologue 168.

The second switch is prepared for gauging to the first switch byunscrewing and removing the finger 189', unscrewing the three bolts 1&3and removing the forward cylinder portion 193 and knob 17S'. The frontwall 177' is also removed. The cylinder 163 is thus ready to be gangedin alignment with the cylinder 168 by screwing the three bolts 133 intothe tapped bores196 formed in the end of the cylinder 168. Theresultantconnection appears as shown in the fragmentary view FiG. 8'.

In order that the finger 181 of the front or. first switch may stillserve to lift all of the cam followers 67g of the ganged combination,means are provided to link the several switch operating shaftsSQgtogether.

This means comprises squaring and extending the front end of each shaft39g as shown at 1117. In the front switch this squared end resides in aclearance bore 198 formed on the interior of the front wall 177. Therear end of each shaft 39g is provided with a square opening 199 (FIG.9) which receives the squared extension 197' of the ganged switch asshown in FiG. 9.

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ing, shaft means mounted in said housing for both rotary and axialmovement, a plurality of leaf spring members mounted in said housing,said leaf spring members being disposed substantially radially withrespect to said shaft, means mounting said leaf spring members to becompressed longitudinally thereby to form an arch, said shaft meanscomprising a portion of enlarged diameter having a plurality of undercutgrooves extending parallel to the axis of said shaft means, a pluralityof cam segments each having a base corresponding to the shape of one ofsaid grooves, and slid axially into one of said grooves to be retainedtherein against radial separation from said shaft means, means forconfining said cam segments in said grooves against axial displacement,the upper portions of said cam segments proportioned to abut one anotherwhen installed in adjacent positions in the same or adjacent saidgrooves so as to form desired circumferential axial cam patterns, aplurality of auxiliary shafts, one for each of said leaf spring members,said auxiliary shafts being journalled in said housing and disposedaround and substantially parallel to said shaft means, a plurality ofcam follower means coupled to respective ones of said auxiliary shaftsfor engaging said cams thereby flexing said leaf spring members to snapthe arch thereof from one position to the other, movable contact meanscarried by said leaf spring members, and stationary contact meanscarried by said housing and by said movable Contact means, toselectively open and close electric circuits, whereby upon movement ofsaid shaft, said leaf spring members are operated from one position toanother.

2. Mechanism in accordance with claim l including ring means disposedcircumjacent said shaft means, means linking said ring means with eachof said auxiliary shafts, and operating means for oscillating said ringmeans about said shaft means, thereby to pivot said linking means andsaid auxiliary shafts and lift said cam follower means away from therespective cam means.

References Cited in the le of this patent UNITED STATES PATENTS1,831,368 Rubel Nov. 10, 1931 1,866,422 Ralph uiy 5, 1932 2,059,712Schellenger Nov. 3, 1936 2,202,698 Latta May 28, 1940 2,603,725 Dietrich.luly 15, 1952 2,825,779 Kelleigh Mar. 4, 1958 2,842,632 Edwards July 8,1958

1. MULTI-CONTACT SWITCH MECHANISM COMPRISING A HOUSING, SHAFT MEANSMOUNTED IN SAID HOUSING FOR BOTH ROTARY AND AXIAL MOVEMENT, A PLURALITYOF LEAF SPRING MEMBERS MOUNTED IN SAID HOUSING, SAID LEAF SPRING MEMBERSBEING DISPOSED SUBSTANTIALLY RADIALLY WITH RESPECT TO SAID SHAFT, MEANSMOUNTING SAID LEAF SPRING MEMBERS TO BE COMPRESSED LONGITUDINALLYTHEREBY TO FORM AN ARCH, SAID SHAFT MEANS COMPRISING A PORTION OFENLARGED DIAMETER HAVING A PLURALITY OF UNDERCUT GROOVES EXTENDINGPARALLEL TO THE AXIS OF SAID SHAFT MEANS, A PLURALITY OF CAM SEGMENTSEACH HAVING A BASE CORRESPONDING TO THE SHAPE OF ONE OF SAID GROOVES,AND SLID AXIALLY INTO ONE OF SAID GROOVES TO BE RETAINED THEREIN AGAINSTRADIAL SEPARATION FROM SAID SHAFT MEANS, MEANS FOR CONFINING SAID CAMSEGMENTS IN SAID GROOVES AGAINST AXIAL DISPLACEMENT, THE UPPER PORTIONSOF SAID CAM SEGMENTS PROPORTIONED TO ABUT ONE ANOTHER WHEN INSTALLED INADJACENT POSITIONS IN THE SAME OR ADJACENT SAID GROOVES SO AS TO FORMDESIRED CIRCUMFERENTIAL AXIAL CAM PATTERNS, A PLURALITY OF AUXILIARYSHAFTS, ONE FOR EACH OF SAID LEAF SPRING MEMBERS, SAID AUXILIARY SHAFTSBEING JOURNALLED IN SAID HOUSING AND DISPOSED AROUND AND SUBSTANTIALLYPARALLEL TO SAID SHAFT MEANS, A PLURALITY OF CAM FOLLOWER MEANS COUPLEDTO RESPECTIVE ONES OF SAID AUXILIARY SHAFTS FOR ENGAGING SAID CAMSTHEREBY FLEXING SAID LEAF SPRING MEMBERS TO SNAP THE ARCH THEREOF FROMONE POSITION TO THE OTHER, MOVABLE CONTACT MEANS CARRIED BY SAID LEAFSPRING MEMBERS, AND STATIONARY CONTACT MEANS CARRIED BY SAID HOUSING ANDBY SAID MOVABLE CONTACT MEANS, TO SELECTIVELY OPEN AND CLOSE ELECTRICCIRCUITS, WHEREBY UPON MOVEMENT OF SAID SHAFT, SAID LEAF SPRING MEMBERSARE OPERATED FROM ONE POSITION TO ANOTHER.